.TH LIBPFM 3  "April, 2022" "" "Linux Programmer's Manual"
.SH NAME
libpfm_intel_spr - support for Intel SapphireRapid core PMU
.SH SYNOPSIS
.nf
.B #include <perfmon/pfmlib.h>
.sp
.B PMU name: spr
.B PMU desc: Intel SapphireRapid
.sp
.SH DESCRIPTION
The library supports the Intel SapphireRapid core PMU. It should be noted that
this PMU model only covers each core's PMU and not the socket level
PMU.

On SapphireRapid, the number of generic counters depends on the Hyperthreading (HT) mode.

The \fBpfm_get_pmu_info()\fR function returns the maximum number
of generic counters in \fBnum_cntrs\fr.

.SH MODIFIERS
The following modifiers are supported on Intel SapphireRapid processors:
.TP
.B u
Measure at user level which includes privilege levels 1, 2, 3. This corresponds to \fBPFM_PLM3\fR.
This is a boolean modifier.
.TP
.B k
Measure at kernel level which includes privilege level 0. This corresponds to \fBPFM_PLM0\fR.
This is a boolean modifier.
.TP
.B i
Invert the meaning of the event. The counter will now count cycles in which the event is \fBnot\fR
occurring. This is a boolean modifier
.TP
.B e
Enable edge detection, i.e., count only when there is a state transition from no occurrence of the event
to at least one occurrence. This modifier must be combined with a counter mask modifier (m) with a value greater or equal to one.
This is a boolean modifier.
.TP
.B c
Set the counter mask value. The mask acts as a threshold. The counter will count the number of cycles
in which the number of occurrences of the event is greater or equal to the threshold. This is an integer
modifier with values in the range [0:255].
.TP
.B ldlat
Pass a latency threshold to the MEM_TRANS_RETIRED:LOAD_LATENCY event.
This is an integer attribute that must be in the range [1:65535]. It is required
for this event.  Note that the event must be used with precise sampling (PEBS).
.TP
.B intx
Monitor the event only when executing inside a transactional memory region (in tx). Event
does not count otherwise. This is a boolean modifiers. Default value is 0.
.TP
.B intxcp
Do not count occurrences of the event when they are inside an aborted transactional memory
region. This is a boolean modifier. Default value is 0.
.TP
.B fe_thres
This modifier is for the FRONTEND_RETIRED event only. It defines the period in core cycles after which the IDQ_*_BUBBLES umask
counts. It acts as a threshold, i.e., at least a period of N core cycles where the frontend did not deliver X uops. It can only
be used with the IDQ_*_BUBBLES umasks. If not specified, the default threshold value is 1 cycle. the valid values are in [1-4095].

.SH OFFCORE_RESPONSE events
Intel SapphireRapid supports two encodings for offcore_response events. In the library, these are called OFFCORE_RESPONSE_0 and OFFCORE_RESPONSE_1.

Those events need special treatment in the performance monitoring infrastructure
because each event uses an extra register to store some settings. Thus, in
case multiple offcore_response events are monitored simultaneously, the operating system needs
to manage the sharing of that extra register.

The offcore_response events are exposed as a normal events by the library. The extra
settings are exposed as regular umasks. The library takes care of encoding the
events according to the underlying kernel interface.

On Intel SapphireRapid unlike older processors, the event is treated as a regular event with a flat set of umasks to choose from.
It is not possible to combine the various requests, supplier, snoop bits anymore. Therefore the
library offers the list of validated combinations as per Intel's official event list.

.SH AUTHORS
.nf
Stephane Eranian <eranian@gmail.com>
.if
.PP
